Investigation of Precipitation Behavior of a Novel Ni-Fe-Based Superalloy during High-Temperature Aging Treatment

Materials, Год журнала: 2024, Номер 17(19), С. 4875 - 4875

Опубликована: Окт. 4, 2024

The precipitation behavior of a novel Ni-Fe-based superalloy developed for advanced ultra-supercritical (A-USC) coal-fired power plant applications during high-temperature aging treatment was investigated. results showed that the major precipitates in alloy were randomly distributed MC carbides, M23C6 carbides at grain boundaries, and γ′-Ni3 (Al, Ti) phase interiors after aging. remained relatively stable both short-term long-term quickly precipitated exhibited discrete distribution boundaries aging, partly into continuous films After uniform precipitation, shape γ′ spherical, size kept increasing with time according to Lifshitz–Slyozov–Wagner (LSW) model. hardness mainly associated γ′; as gradually precipitated, steadily increased; complete increased, first increased then decreased, reaching peak when average radius achieved critical size. In addition, abnormal coarsening coarsened actually precipitate-free zones (PFZs) elongated rod-like particles inside identified precipitates. mechanism strain-induced boundary migration discontinuous reaction is proposed formation PFZs. Furthermore, PFZs considered be potential crack sources creep rupture test, leading earlier failure material.

Язык: Английский

---

Insight into the enhancing mechanical strength of CoCrNi-TiC composites fabricated by laser powder bed fusion

Materials Science and Engineering A, Год журнала: 2025, Номер 924, С. 147786 - 147786

Опубликована: Янв. 2, 2025

Язык: Английский

---

The Influence of Sample Microfabrication and Annealing on the Mechanical Strain–Stress Behavior of Stainless Steels and Corrosion Resistant Aluminum Alloys in Micro-Tensile Tests

Micromachines, Год журнала: 2025, Номер 16(3), С. 309 - 309

Опубликована: Март 6, 2025

Miniaturized components for enhanced integrated functionality or thin sheets lightweight applications often consist of face-centered cubic metals. They exhibit good strength, corrosion resistance, formability and recyclability. Microfabrication technologies, however, may introduce cold work detrimental heat-induced lattice defects into the material, with consequences mechanical properties. Austenitic stainless steels (1.4310, 1.4301) aluminum alloys (EN AW-5005-H24, EN AW-6082-T6) were selected this study. The influence pulsed fiber laser cutting, microwaterjet annealing on strain–stress behavior was investigated. micro-tensile test setup comprised a flex-structure force sensor, extensometer, dedicated sample holder. Fiber cut 1.4310 samples exhibited early failure at low fracture strain in narrow shear band zones. zones detectable surface, extensometer images, horizontal sections stress–strain curves, microstructure. Inside zones, grains strongly elongated numerous parallel planar defects. Heat-induced chromium carbides, combination stacking fault energy (SFE) elevated carbon content, favored zone formation 1.4310. In contrast, high SFE materials AW-5005-H24 AW-6082-T6, as well low-carbon austenitic steel 1.4301, uniform plastic deformation.

Язык: Английский

---

Incubation of Horseradish Peroxidase near 50 Hz AC Equipment Promotes Its Disaggregation and Enzymatic Activity

Micromachines, Год журнала: 2025, Номер 16(3), С. 344 - 344

Опубликована: Март 19, 2025

Low-frequency electromagnetic fields, induced by alternating current (AC)-based equipment such as transformers, are known to influence the physicochemical properties and function of enzymes, including their catalytic activity. Herein, we have investigated how incubation near a 50 Hz AC autotransformer influences horseradish peroxidase (HRP), atomic force microscopy (AFM) spectrophotometry. We found that half-hour-long enzyme above coil loaded promoted adsorption monomeric form HRP on mica, enhancing number adsorbed particles two orders magnitude in comparison with control sample. Most interestingly, switched-off transformer, which was unplugged from mains power supply, for same period time also cause disaggregation enzyme. Notably, an increase activity against ABTS observed both cases. hope interesting effects reported will emphasize importance consideration low-frequency fields enzymes design laboratory industrial intended operation systems. The revealed our study indicate proper shielding AC-based transformers order avoid undesirable these humans.

Язык: Английский

---

Effect of Arc Current on the Microstructure of AlTiN-Coated Tools and Milling of 304 Stainless Steel

Coatings, Год журнала: 2024, Номер 14(6), С. 704 - 704

Опубликована: Июнь 4, 2024

304 stainless steel demonstrates a low thermal conductivity and work hardening characteristics, resulting in its processing, will adhere to the tip of tool; as well phenomenon chipping, shortening life tool. AlTiN coatings are representative applied carbide tools. In this paper, with different arc current processes were deposited on milling inserts using ion plating. The microstructure, mechanical properties, properties investigated by SEM, EDS, XRD, scratch meter, friction wear vertical machining center. findings revealed that all displayed columnar crystal growth, free from cracks voids. With an increasing current, there was notable increase surface droplets, pits, coating thickness. at 140 A showed pronounced (200) orientation preference. adhesion force peaked 56.0 N subsequent decline, coefficient hit lowest point 0.429 A, contrasting highest value 0.55 160 A. After 39 min dry milling, tool exhibited minimal 0.196 mm, just below 0.2 mm failure threshold, indicating superior performance setting.

Язык: Английский

---

Study on High Temperature Properties of Yttrium-Modified Aluminide Coating on K444 Alloy by Chemical Vapor Deposition

Coatings, Год журнала: 2024, Номер 14(6), С. 750 - 750

Опубликована: Июнь 13, 2024

This work aims to explore a method of improving the high-temperature oxidation resistance and thermal corrosion hollow blade gas turbine. The yttrium-modified aluminide coating was prepared on surface nickel-based superalloy K444 by chemical vapor deposition (CVD). microstructure, high temperature resistance, modified deposited at 950 °C, 1000 1050 °C were compared. microstructure morphology coatings observed analyzed XRD, SEM, EDS. results showed that adding yttrium changing had no effect double-layer structure (outer layer diffusion layer) coating. Compared with yttrium, greater thickness. When time 2 h, thickness increased 33% compared single three groups are better than hot both °C. higher temperature, content coating, faster film-forming speed α-Al2O3,

Язык: Английский

---

Characterizing Short-Time Aging Precipitation Behavior of a Novel Nickel–Iron-Based Alloy via Electrical Performance

Materials, Год журнала: 2024, Номер 17(16), С. 4143 - 4143

Опубликована: Авг. 21, 2024

In this paper, the precipitation behavior and its effect on resistivity in a new type of nickel–iron-based alloy during short-term aging were investigated. During process, γ′ phase increases average size decreases number, with area fraction fluctuating over time. This fluctuation is caused by mismatch redissolution growth rates phase. As increases, content solute atoms matrix that scatter electrons decreases, lowering alloy. Additionally, continuous M23C6 at grain boundaries causes to gradually increase. paper explains total amount proposes method for characterizing novel using relative trend changes.

Язык: Английский

---

Research on Key Technologies of Jewelry Design and Manufacturing Based on 3D Printing Technology

Coatings, Год журнала: 2024, Номер 14(6), С. 701 - 701

Опубликована: Июнь 3, 2024

In conjunction with the swift enhancement of China’s economic prowess, demand for jewelry among populace is gradually evolving towards personalized, customized, and intricate designs. Traditional manufacturing approaches are increasingly inadequate to meet these demands. However, advent 3D printing technology presents a viable solution direct fabrication such sophisticated jewelry. To this end, conceptualization personalized inspiration initiated, followed by implementation parametric design using SolidWorks 2018 software. Subsequently, employed materialize directly. Results indicate that “Guardian” model, crafted through modeling method, exhibits commendable design, adheres processing requirements following comprehensive risk analysis. The strategic adjustment jewelry’s position effectively reduces required support, circumventing necessity adding support critical surfaces. surface Selective Laser Melting (SLM)-manufactured boasts lustrous finish, showcasing optimal overlap between pillars excellent connectivity pores. Minimal powder adherence on observed, enabling utilization post-sandblasting, polishing, plating. This establishes solid foundation application SLM-manufactured

Язык: Английский

---

Cu- and Fe-Doped Ni-Mn-Sn Shape Memory Alloys with Enhanced Mechanical and Magnetocaloric Properties

Materials, Год журнала: 2024, Номер 17(13), С. 3172 - 3172

Опубликована: Июнь 28, 2024

Ni-Mn-Sn-based ferromagnetic shape memory alloys (FSMAs) are multifunctional materials that promising for solid-state refrigeration applications based on the magnetocaloric effect (MCE) and elastocaloric (eCE). However, a combination of excellent multi-caloric properties, suitable operating temperatures, mechanical properties cannot be well achieved in these materials, posing challenge their practical application. In this work, we systematically study phase transformations magnetic Ni50−xMn38Sn12Cux (x = 0, 2, 3, 4, 5, 6) Ni50−yMn38Sn12Fey (y 1, 5) alloys, magnetic-structural diagrams alloy systems reported. The influences fourth-element doping transitions elucidated by first-principles calculations. This work demonstrates FSMA is effective developing multicaloric refrigerants refrigeration.

Язык: Английский

---

Systematic First-Principles Investigations of the Nucleation, Growth, and Surface Properties of Al11RE3 Second-Phase Particles in Al-Based Alloys

Coatings, Год журнала: 2024, Номер 14(8), С. 983 - 983

Опубликована: Авг. 4, 2024

At room temperature, Al alloys have excellent mechanical properties and are widely used in automotive, electronics, aerospace other fields, but it is difficult to maintain this advantage the middle high temperature ranges. To address issue, second-phase Al11RE3 (RE represents rare earth element) was introduced into a Al-Mg-RE alloy as its primary constituent. By incorporating RE elements additives, material exhibits exceptional thermal at elevated temperatures. Based on first principles quasi-harmonic approximation (QHA), nucleation growth mechanism surface of were studied paper. The interfacial energy γα/β, strain ΔECS chemical driving force ΔGV obtained. Models1, 4, 6 better para-site connections than inter-site connections. It found that resistances particle nucleation, interface γα/β ΔECS, increase then decrease with increased atomic number REs, they much smaller ΔGV. A reduced diminished radius R* more favorable for process nucleation. addition Sc most unfavorable La has strongest nucleating ability, which gradually decreases lanthanide element increases. ability phase increasing consistent experiments. also increases indicating Since easier compared model4 6, model1 smallest increment. Thus, prominent mechanism. In study, diffusion activation Q, faster rate matrix, hence higher coiling rate, promotes particles. Q sequentially from Ce number. coarsening KLSW models1, promoted This paper intended provide solid theoretical basis production application aluminum

Язык: Английский

---